CA2179387A1 - A method and an arrangement for generating a ringing signal - Google Patents
A method and an arrangement for generating a ringing signalInfo
- Publication number
- CA2179387A1 CA2179387A1 CA002179387A CA2179387A CA2179387A1 CA 2179387 A1 CA2179387 A1 CA 2179387A1 CA 002179387 A CA002179387 A CA 002179387A CA 2179387 A CA2179387 A CA 2179387A CA 2179387 A1 CA2179387 A1 CA 2179387A1
- Authority
- CA
- Canada
- Prior art keywords
- subscriber line
- interface circuit
- current
- line interface
- ringing signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M19/00—Current supply arrangements for telephone systems
- H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Interface Circuits In Exchanges (AREA)
- Devices For Supply Of Signal Current (AREA)
- Burglar Alarm Systems (AREA)
- Reduction Or Emphasis Of Bandwidth Of Signals (AREA)
- Telephonic Communication Services (AREA)
Abstract
To generate a ringing signal by means of a subscriber line interface circuit having two final stages (A), each for supplying an individual subscriber line wire (LA, LB), one (LA) of the subscriber line wires is connected to one of the input terminals of an operational amplifier, the other input terminal of which being connected to the interconnecting point between two series connected resistors having the same resistance, the output terminal of the operational amplifier being connected, via a first resistor (2T), to a current input terminal (R) of the subscriber line interface circuit for generating a first current, while a signal generator (U), via a second resistor (ZR), is also connected to said current input terminal (R) for generating a second current, said final stages (A) of the subscriber line interface circuit being supplied with current from said current input terminal (R) to drive the final stages (A) to generate the ringing signal.
Description
WO95/20290 21 793~7 r~ 7 A MElElOD AND AN jriDD7~ ~ FOR GENEDATING A RINGING SIGNAL
TECHNIc'AL FIELD
5 The invention relates to a method of generating a ringing signal by means of a subscriber line interface circuit, and also to an arr~ngf~- L for generating a ringing signal by means of a subscriber line interface circuit having two final stages, each for supplying an individual subscriber line wire.
DESCRTPTION OF THE l~Af- - ART
The costs of installing new copper lines is increasing and constitutes a large part of the total installation costs. The 15 capacity required by tomorrow's information community will be greater than what can be managed by present-day copper/coaxial cable systems. New telephone services will be illl.L~,.luced, therewith increasing the amount of information that need be transmitted and cable television ~works will be extended.
20 Installation costs could be lowered considerably, by transmit-ting the telephone services and the television signals on one and the same fibre. The last piece to the subscriber, however, is still in the form of a copper cable, even though the distance is considerably shorter than in the case of standard 25 telephone lines.
short lines do not reguire egually as large ringing signals from the line interface board as long lines, 6ince in princi-ple there is no voltage division between the bells and the 30 telephone lines.
DTct~rncllDr~ OF THE lh~n lC
The object of the invention is to generate the ringing signal 35 at a lower voltage than has hitherto been normal.
WO 95120290 ~l ~~ 17 21 7~387 This is achieved with an, inventive method having the charac-teristic features set forth in Claim 1, and with an inventive arrAn~, L having the characteristic features set forth in Claim 3.
A ringing relay is not required when the ` ringing signal is generated by means of the subscriber linè interface circuit in accordance with the invention, th;ëreby f~nh~nc; n~ the reliability of the line module. This is an advantage, since lO the line module will become less ~!C~q; hl e due to being placed with or in the proximity of the subscriber.
BRIE F DE SCRIPTION OF T~ nl~
15 The invention will now be cle~rr; h~d in more detail w~th reference to the AC , nying drawings, in which Fig. 1 is a block schematic which illustrates generally a FITL-system (Fibre In The Loop-system):
Fig. 2 illustrates one exemplifying ~ ' of the inven-20tive arrangement;
Fig. 3 iIIustrates a subscriber line interface circuit equivalent of two f inal stages;
Fig. 4 illustrates the two-wire voltage when ringing;
Fig. 5 illustrates another exemplifying: ' 'i L of the 25 inventive arrAn~, ~; and Fig. 6 illustrates activation of the Fig. 5 ~mhofl;- L on an existing test board.
BFST MODE S OF CARRYING OUT ~ lh Fig. 1 illustrates the ~.ull~,LL~ ion of a general FITL-system in which a digital host terminal HDT is cnnnert~l to the local telephone exchange or switching centre. The digital host terminal ~DT controls a plurality of optical network units ONU
35 through the medium of an optical, passive distribution network PDN. Conversion from optical signals to electrical siqnals and A/D-conversion take place in the optical network units ONU,
TECHNIc'AL FIELD
5 The invention relates to a method of generating a ringing signal by means of a subscriber line interface circuit, and also to an arr~ngf~- L for generating a ringing signal by means of a subscriber line interface circuit having two final stages, each for supplying an individual subscriber line wire.
DESCRTPTION OF THE l~Af- - ART
The costs of installing new copper lines is increasing and constitutes a large part of the total installation costs. The 15 capacity required by tomorrow's information community will be greater than what can be managed by present-day copper/coaxial cable systems. New telephone services will be illl.L~,.luced, therewith increasing the amount of information that need be transmitted and cable television ~works will be extended.
20 Installation costs could be lowered considerably, by transmit-ting the telephone services and the television signals on one and the same fibre. The last piece to the subscriber, however, is still in the form of a copper cable, even though the distance is considerably shorter than in the case of standard 25 telephone lines.
short lines do not reguire egually as large ringing signals from the line interface board as long lines, 6ince in princi-ple there is no voltage division between the bells and the 30 telephone lines.
DTct~rncllDr~ OF THE lh~n lC
The object of the invention is to generate the ringing signal 35 at a lower voltage than has hitherto been normal.
WO 95120290 ~l ~~ 17 21 7~387 This is achieved with an, inventive method having the charac-teristic features set forth in Claim 1, and with an inventive arrAn~, L having the characteristic features set forth in Claim 3.
A ringing relay is not required when the ` ringing signal is generated by means of the subscriber linè interface circuit in accordance with the invention, th;ëreby f~nh~nc; n~ the reliability of the line module. This is an advantage, since lO the line module will become less ~!C~q; hl e due to being placed with or in the proximity of the subscriber.
BRIE F DE SCRIPTION OF T~ nl~
15 The invention will now be cle~rr; h~d in more detail w~th reference to the AC , nying drawings, in which Fig. 1 is a block schematic which illustrates generally a FITL-system (Fibre In The Loop-system):
Fig. 2 illustrates one exemplifying ~ ' of the inven-20tive arrangement;
Fig. 3 iIIustrates a subscriber line interface circuit equivalent of two f inal stages;
Fig. 4 illustrates the two-wire voltage when ringing;
Fig. 5 illustrates another exemplifying: ' 'i L of the 25 inventive arrAn~, ~; and Fig. 6 illustrates activation of the Fig. 5 ~mhofl;- L on an existing test board.
BFST MODE S OF CARRYING OUT ~ lh Fig. 1 illustrates the ~.ull~,LL~ ion of a general FITL-system in which a digital host terminal HDT is cnnnert~l to the local telephone exchange or switching centre. The digital host terminal ~DT controls a plurality of optical network units ONU
35 through the medium of an optical, passive distribution network PDN. Conversion from optical signals to electrical siqnals and A/D-conversion take place in the optical network units ONU,
2 1 7 9 3 g 7 r~ r ~ 17 among other things. The optical network units ONU communicate with a network interf ace NI in a known manner, through the medium of copper wires . Normal telephone services, ref erenced POTS in Fig. 1, and video services are obtained by a number 5 of subscribers via the interface NI.
A 100 ohms line ~.ULL~ JUlldS to 550 m of a 0.5 mm' AWG24-cable.
A line having a length of 1 km will there~ore ~ uLLe;~{~ulld to 180 ohms of such a cable.
In the specification TA-NWT-OOO909 from Bellcore, it is cnn~ red that the ~ phnnF~ line will not exceed 500 feet, which is less than 30 ohms. A line having a length of 1 km must therefore be considered acceptable.
Fig. 2 illustrates a first ~ of the inventive arrangement in a subscriber line interface circuit having two final stages A, each for supplying the a-wire and b-wire of respective subscriber line wires LA and LB of a telephone set.
In Fig. 2, the reference signs rsl and rs2 identify protective resistors, while reference signs rll and rl2 identify line resistances .
25 According to the invention, one of the subscriber line wires is ronnect-~ to one input terminal of an operational amplifi-er, the other input of which is connected to the interconnect-ing point between two series-connected resistors which have mutually the same resistance (400 k~ and which are connected 30 between earth and the supply voltage VBB of the subscriber line interface circuit.
The output t~rmin~l of the operational amplifier is connected to the current input t~rminS~l R of the subscriber line 35 interface circuit via a resistor ZT. A 20 Hz signal generator U is also connected to the current input t~nin5~ R, via a resistor ZR . The current f lowing through the current input Wogs/20290 21 7 9 3 87 F~l S ~ 7 ~
t~rm; nAl R supplies the final stages A of the subscriber line interface circuit, to drive the final stages to generate the ringing signal.
5 With a supply voltage VBB of -80 V, there is obtained a voltage having an effective value of 40 V Qver 5 REN at a line load of lO0 ohms and a protective resistance of 2 x 50 ohms.
The ringing signal is hr-lAn--~rl around VBB/2 (no offset current ) .
The circuit operates as follows:
The input signal, which has an effective value of about l V, is generated centrally by the signal generator U. The amplifi-15 cation 4-wire --> 2-wire in an open line is set by the quotient between ZT x 32 x 2 and the resistor ZR. The current from the input siqnal and the feedback to the R-input is amplified l,OoO times to the outputs LA and LB of the final stages A. The current delivered to I,A is phase-shifted through 20 180, whereas the current delivered to LB is in phase. The dLrect current - ^nt of the signal fed back to the operational amplifier i8 subtracted by adding half the supply voltage VBB in the operational amplifier.
25 The internal longitudinal loop centres LA and LB symmQtrically around half the supply voltage VBB, as evident from Fig. 4.
Bellcore's requirement cnnc~rninq the generation of a ringing signal is not fulf illed completely with the aid of the 30 invention, but that certain eYceptions must be made without jeopardizing the subscriber ringing function.
The ringing signal centred around half the supply voltage VBB
is qenerated over the outputs LA and LB on the a-wire and b-35 wire respectively. The a-wire shall lie "close to" earth potential in the ringing pause and the b-wire shall lie on a negative voltage which is equal to the voltage in the rest ~ WO 95/20290 2 1 7 9 3 8 7 ~; r~ 7 state, the supply voltage being equal to -80 V.
The supply voltage is thus lower than in the c2se of unbal-anced ringing.
Pig. 3 lllustrates a subscriber line interface circuit equivalent of two f inal stages, wherein ZUT signif ies the output i , ' - which is roughly equal to 2 x 70 ohms, RS
signif ies the protective resistances, which are roughly equal 10 to 100 ohms, ZL signlfies the line i -' , which lies between about 0-200 ohms, ZBEI.L signifies the imp~-~ance of the bell, this i -'---_ lying between about 1.4 and 7 kohm, and wherein LIC signifies the line interface board, and ug signifies the ringing yell~LClLUL voltage.
Fig . 5 illustrates a second ~ i r L of the invention in which an existing subscriber line interface board is used to generate the ringing signal with the aid of a subscriber line interface circuit.
The voltage across RINGX, which ~;UL ' eD~ ds to L8 in Fig. 2, is divided by resistors RTRl and RTR2. The direct current L is removed with the aid of the capacitor CAC. The feedback signal is then buffered via the operational amplifier 25 Op2 and then applied to the current terminal RSN, which cuLLeD~ulldD to R in Fig. 2, via the resistor Rep, which .eD~JUlldS to ZT in Fig. 2. Since the application is effected on an existing solution, a bias current and part of the input signal are added so as to remove the current that arrives from 30 the direct current loop consisting of the resistors Rbias, R23 and R24. The transistors Tl and T2 close the ringing function when a logic 1 occurs across C3.
Fig. 6 illustrates an example of where and how the ~ L
35 illustrated in Fig. 5 is set up on an existing test board.
The lower ringing signal voltages on the line interface board W095120290 2 ~ 7~387 P~ 7 ~
in accordance with the invention thus enable ringing to be effected with the aid of an integrated subscriber line interface circuit, thereby eliminating the need for a standard ringing relay. In order to place the lowest possible voltage requirements on the ringing signal, ~there is utilized in o~ lce with the invention baianced ringing which is centred around half the supply voltage with low output -' n~, in comparison with a conventional ringing genera-tor .
A 100 ohms line ~.ULL~ JUlldS to 550 m of a 0.5 mm' AWG24-cable.
A line having a length of 1 km will there~ore ~ uLLe;~{~ulld to 180 ohms of such a cable.
In the specification TA-NWT-OOO909 from Bellcore, it is cnn~ red that the ~ phnnF~ line will not exceed 500 feet, which is less than 30 ohms. A line having a length of 1 km must therefore be considered acceptable.
Fig. 2 illustrates a first ~ of the inventive arrangement in a subscriber line interface circuit having two final stages A, each for supplying the a-wire and b-wire of respective subscriber line wires LA and LB of a telephone set.
In Fig. 2, the reference signs rsl and rs2 identify protective resistors, while reference signs rll and rl2 identify line resistances .
25 According to the invention, one of the subscriber line wires is ronnect-~ to one input terminal of an operational amplifi-er, the other input of which is connected to the interconnect-ing point between two series-connected resistors which have mutually the same resistance (400 k~ and which are connected 30 between earth and the supply voltage VBB of the subscriber line interface circuit.
The output t~rmin~l of the operational amplifier is connected to the current input t~rminS~l R of the subscriber line 35 interface circuit via a resistor ZT. A 20 Hz signal generator U is also connected to the current input t~nin5~ R, via a resistor ZR . The current f lowing through the current input Wogs/20290 21 7 9 3 87 F~l S ~ 7 ~
t~rm; nAl R supplies the final stages A of the subscriber line interface circuit, to drive the final stages to generate the ringing signal.
5 With a supply voltage VBB of -80 V, there is obtained a voltage having an effective value of 40 V Qver 5 REN at a line load of lO0 ohms and a protective resistance of 2 x 50 ohms.
The ringing signal is hr-lAn--~rl around VBB/2 (no offset current ) .
The circuit operates as follows:
The input signal, which has an effective value of about l V, is generated centrally by the signal generator U. The amplifi-15 cation 4-wire --> 2-wire in an open line is set by the quotient between ZT x 32 x 2 and the resistor ZR. The current from the input siqnal and the feedback to the R-input is amplified l,OoO times to the outputs LA and LB of the final stages A. The current delivered to I,A is phase-shifted through 20 180, whereas the current delivered to LB is in phase. The dLrect current - ^nt of the signal fed back to the operational amplifier i8 subtracted by adding half the supply voltage VBB in the operational amplifier.
25 The internal longitudinal loop centres LA and LB symmQtrically around half the supply voltage VBB, as evident from Fig. 4.
Bellcore's requirement cnnc~rninq the generation of a ringing signal is not fulf illed completely with the aid of the 30 invention, but that certain eYceptions must be made without jeopardizing the subscriber ringing function.
The ringing signal centred around half the supply voltage VBB
is qenerated over the outputs LA and LB on the a-wire and b-35 wire respectively. The a-wire shall lie "close to" earth potential in the ringing pause and the b-wire shall lie on a negative voltage which is equal to the voltage in the rest ~ WO 95/20290 2 1 7 9 3 8 7 ~; r~ 7 state, the supply voltage being equal to -80 V.
The supply voltage is thus lower than in the c2se of unbal-anced ringing.
Pig. 3 lllustrates a subscriber line interface circuit equivalent of two f inal stages, wherein ZUT signif ies the output i , ' - which is roughly equal to 2 x 70 ohms, RS
signif ies the protective resistances, which are roughly equal 10 to 100 ohms, ZL signlfies the line i -' , which lies between about 0-200 ohms, ZBEI.L signifies the imp~-~ance of the bell, this i -'---_ lying between about 1.4 and 7 kohm, and wherein LIC signifies the line interface board, and ug signifies the ringing yell~LClLUL voltage.
Fig . 5 illustrates a second ~ i r L of the invention in which an existing subscriber line interface board is used to generate the ringing signal with the aid of a subscriber line interface circuit.
The voltage across RINGX, which ~;UL ' eD~ ds to L8 in Fig. 2, is divided by resistors RTRl and RTR2. The direct current L is removed with the aid of the capacitor CAC. The feedback signal is then buffered via the operational amplifier 25 Op2 and then applied to the current terminal RSN, which cuLLeD~ulldD to R in Fig. 2, via the resistor Rep, which .eD~JUlldS to ZT in Fig. 2. Since the application is effected on an existing solution, a bias current and part of the input signal are added so as to remove the current that arrives from 30 the direct current loop consisting of the resistors Rbias, R23 and R24. The transistors Tl and T2 close the ringing function when a logic 1 occurs across C3.
Fig. 6 illustrates an example of where and how the ~ L
35 illustrated in Fig. 5 is set up on an existing test board.
The lower ringing signal voltages on the line interface board W095120290 2 ~ 7~387 P~ 7 ~
in accordance with the invention thus enable ringing to be effected with the aid of an integrated subscriber line interface circuit, thereby eliminating the need for a standard ringing relay. In order to place the lowest possible voltage requirements on the ringing signal, ~there is utilized in o~ lce with the invention baianced ringing which is centred around half the supply voltage with low output -' n~, in comparison with a conventional ringing genera-tor .
Claims (4)
1. A method of generating a ringing signal by means of a subscriber line interface circuit, characterized by - applying a voltage which is a function of the output voltage of the subscriber line interface circuit over a first resistor (ZT), such as to generate a first current;
- applying the output voltage of a signal generator (U) over a second resistor (ZR), such as to generate a second current;
and - adding the first and the second currents together to obtain an input current to the final stages (A) of the subscriber line interface circuit so as to drive said final stages to generate the ringing signal.
- applying the output voltage of a signal generator (U) over a second resistor (ZR), such as to generate a second current;
and - adding the first and the second currents together to obtain an input current to the final stages (A) of the subscriber line interface circuit so as to drive said final stages to generate the ringing signal.
2. A method according to Claim 1, characterized in that the voltage that is a function of the output voltage of the subscriber line interface circuit is comprised of the output voltage of said subscriber line interface circuit from which its direct current component has been substracted.
3. An arrangement for generating a ringing signal by means of a subscriber line interface circuit having two final stages (A), each for supplying an individual subscriber line wire (LA, LB), characterized in that one subscriber line wire (LA) is connected to one input of an operational amplifier whose other input is connected to the interconnecting point between two series-connected resistors having mutually the same resistance; in that the output of the operational amplifier is connected to a current input terminal (R) of the subscriber line interface circuit via a first resistor (ZT); and in that a signal generator (U) is also connected to said current input terminal (R) via a second resistor (ZR), wherein the current input terminal (R) functions to supply current to the final stages (A) to drive said stages to generate the ringing signal.
4. An arrangement according to Claim 3, characterized in that the two resistors of mutually equal resistance are connected between earth and the supply voltage (VBB) of the subscriber line interface circuit.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE9400185-6 | 1994-01-21 | ||
| SE9400185A SE502276C2 (en) | 1994-01-21 | 1994-01-21 | Method and apparatus for generating a ring signal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2179387A1 true CA2179387A1 (en) | 1995-07-27 |
Family
ID=20392646
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002179387A Abandoned CA2179387A1 (en) | 1994-01-21 | 1995-01-19 | A method and an arrangement for generating a ringing signal |
Country Status (15)
| Country | Link |
|---|---|
| US (1) | US5553132A (en) |
| EP (1) | EP0740881B1 (en) |
| JP (1) | JP3457674B2 (en) |
| KR (1) | KR100265481B1 (en) |
| CN (1) | CN1083205C (en) |
| AT (1) | ATE230537T1 (en) |
| BR (1) | BR9506450A (en) |
| CA (1) | CA2179387A1 (en) |
| DE (1) | DE69529275T2 (en) |
| FI (1) | FI962918A (en) |
| MX (1) | MX9602380A (en) |
| NO (1) | NO314870B1 (en) |
| SE (1) | SE502276C2 (en) |
| TW (1) | TW255085B (en) |
| WO (1) | WO1995020290A1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6167135A (en) * | 1995-12-01 | 2000-12-26 | Telefonaktiebolaget Lm Ericsson | Method and apparatus for generating a ringing signal |
| SE506296C2 (en) * | 1995-12-01 | 1997-12-01 | Ericsson Telefon Ab L M | Method and apparatus for generating a ring signal |
| CN1087546C (en) * | 1998-08-15 | 2002-07-10 | 深圳市安圣电气有限公司 | Secondary signal switchover circuit for small power ringing current generator |
| CN1063305C (en) * | 1998-08-15 | 2001-03-14 | 深圳市华为电气股份有限公司 | Secondary power tube driving circuit for medium and large power ringing current converter |
| CN1057183C (en) * | 1998-08-15 | 2000-10-04 | 深圳市华为电气股份有限公司 | Slow-start and over-current protection circuit for ringing current generator |
| US6282238B1 (en) | 1999-05-28 | 2001-08-28 | 3Com Corporation | Adapter card that selects between an ISDN interface and an analog modem interface |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3689700A (en) * | 1970-09-21 | 1972-09-05 | Lear Siegler Inc | Subscriber loop extension unit |
| US3723662A (en) * | 1971-12-09 | 1973-03-27 | Gte Automatic Electric Lab Inc | D.c. compensated subscriber interface transformer circuit for telephone system |
| IT1079588B (en) * | 1977-02-14 | 1985-05-13 | Sits Soc It Telecom Siemens | STATIC CALL GENERATOR FOR TELECOMMUNICATIONS SYSTEMS |
| NL8000859A (en) * | 1980-02-12 | 1981-09-01 | Philips Nv | DEVICE FOR SUPPLYING A CURRENT VOLTAGE TO A SUBSCRIPTION LINE. |
| US4431868A (en) * | 1981-07-09 | 1984-02-14 | International Telephone And Telegraph Corporation | Solid state telephone line interface circuit with ringing capability |
| SE453240B (en) * | 1986-05-06 | 1988-01-18 | Ericsson Telefon Ab L M | DEVICE IN A TELECOMMUNICATION SYSTEM FOR POWERING A PHONE DEVICE |
-
1994
- 1994-01-21 SE SE9400185A patent/SE502276C2/en not_active IP Right Cessation
-
1995
- 1995-01-19 EP EP95907185A patent/EP0740881B1/en not_active Expired - Lifetime
- 1995-01-19 AT AT95907185T patent/ATE230537T1/en not_active IP Right Cessation
- 1995-01-19 CA CA002179387A patent/CA2179387A1/en not_active Abandoned
- 1995-01-19 KR KR1019960703637A patent/KR100265481B1/en not_active IP Right Cessation
- 1995-01-19 WO PCT/SE1995/000047 patent/WO1995020290A1/en active IP Right Grant
- 1995-01-19 MX MX9602380A patent/MX9602380A/en unknown
- 1995-01-19 BR BR9506450A patent/BR9506450A/en not_active IP Right Cessation
- 1995-01-19 CN CN95191172.4A patent/CN1083205C/en not_active Expired - Lifetime
- 1995-01-19 JP JP51950795A patent/JP3457674B2/en not_active Expired - Lifetime
- 1995-01-19 DE DE69529275T patent/DE69529275T2/en not_active Expired - Lifetime
- 1995-01-20 US US08/375,687 patent/US5553132A/en not_active Expired - Lifetime
- 1995-01-20 TW TW084100489A patent/TW255085B/zh not_active IP Right Cessation
-
1996
- 1996-07-15 NO NO19962960A patent/NO314870B1/en not_active IP Right Cessation
- 1996-07-19 FI FI962918A patent/FI962918A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| SE502276C2 (en) | 1995-09-25 |
| JP3457674B2 (en) | 2003-10-20 |
| CN1083205C (en) | 2002-04-17 |
| FI962918A0 (en) | 1996-07-19 |
| TW255085B (en) | 1995-08-21 |
| FI962918A (en) | 1996-07-19 |
| KR100265481B1 (en) | 2000-09-15 |
| US5553132A (en) | 1996-09-03 |
| EP0740881A1 (en) | 1996-11-06 |
| DE69529275T2 (en) | 2003-08-28 |
| NO314870B1 (en) | 2003-06-02 |
| BR9506450A (en) | 1997-09-02 |
| ATE230537T1 (en) | 2003-01-15 |
| CN1138399A (en) | 1996-12-18 |
| NO962960L (en) | 1996-07-15 |
| DE69529275D1 (en) | 2003-02-06 |
| MX9602380A (en) | 1997-04-30 |
| NO962960D0 (en) | 1996-07-15 |
| SE9400185L (en) | 1995-07-22 |
| SE9400185D0 (en) | 1994-01-21 |
| WO1995020290A1 (en) | 1995-07-27 |
| EP0740881B1 (en) | 2003-01-02 |
| JPH09508244A (en) | 1997-08-19 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |